[NET]: Make the loopback device per network namespace.

This patch makes loopback_dev per network namespace.  Adding
code to create a different loopback device for each network
namespace and adding the code to free a loopback device
when a network namespace exits.

This patch modifies all users the loopback_dev so they
access it as init_net.loopback_dev, keeping all of the
code compiling and working.  A later pass will be needed to
update the users to use something other than the initial network
namespace.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 17 insertions, 17 deletions

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index b43574f73375..6d5c3c299148 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -2410,7 +2410,7 @@ static int addrconf_ifdown(struct net_device *dev, int how)
 
         ASSERT_RTNL();
 
-        if (dev == loopback_dev && how == 1)
+        if (dev == init_net.loopback_dev && how == 1)
                 how = 0;
 
         rt6_ifdown(dev);
@@ -4212,19 +4212,19 @@ int __init addrconf_init(void)
          * device and it being up should be removed.
          */
         rtnl_lock();
-        if (!ipv6_add_dev(loopback_dev))
+        if (!ipv6_add_dev(init_net.loopback_dev))
                 err = -ENOMEM;
         rtnl_unlock();
         if (err)
                 return err;
 
-        ip6_null_entry.u.dst.dev = loopback_dev;
-        ip6_null_entry.rt6i_idev = in6_dev_get(loopback_dev);
+        ip6_null_entry.u.dst.dev = init_net.loopback_dev;
+        ip6_null_entry.rt6i_idev = in6_dev_get(init_net.loopback_dev);
 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
-        ip6_prohibit_entry.u.dst.dev = loopback_dev;
-        ip6_prohibit_entry.rt6i_idev = in6_dev_get(loopback_dev);
-        ip6_blk_hole_entry.u.dst.dev = loopback_dev;
-        ip6_blk_hole_entry.rt6i_idev = in6_dev_get(loopback_dev);
+        ip6_prohibit_entry.u.dst.dev = init_net.loopback_dev;
+        ip6_prohibit_entry.rt6i_idev = in6_dev_get(init_net.loopback_dev);
+        ip6_blk_hole_entry.u.dst.dev = init_net.loopback_dev;
+        ip6_blk_hole_entry.rt6i_idev = in6_dev_get(init_net.loopback_dev);
 #endif
 
         register_netdevice_notifier(&ipv6_dev_notf);
@@ -4279,7 +4279,7 @@ void __exit addrconf_cleanup(void)
                         continue;
                 addrconf_ifdown(dev, 1);
         }
-        addrconf_ifdown(loopback_dev, 2);
+        addrconf_ifdown(init_net.loopback_dev, 2);
 
         /*
          *      Check hash table.
diff --git a/net/ipv6/netfilter/ip6t_REJECT.c b/net/ipv6/netfilter/ip6t_REJECT.c
index 50860531cd3c..3fd08d5567a6 100644
--- a/net/ipv6/netfilter/ip6t_REJECT.c
+++ b/net/ipv6/netfilter/ip6t_REJECT.c
@@ -167,7 +167,7 @@ static inline void
 send_unreach(struct sk_buff *skb_in, unsigned char code, unsigned int hooknum)
 {
         if (hooknum == NF_IP6_LOCAL_OUT && skb_in->dev == NULL)
-                skb_in->dev = loopback_dev;
+                skb_in->dev = init_net.loopback_dev;
 
         icmpv6_send(skb_in, ICMPV6_DEST_UNREACH, code, 0, NULL);
 }
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index a7a21a7ba790..6ff19f9eb9ee 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -221,8 +221,8 @@ static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
         struct rt6_info *rt = (struct rt6_info *)dst;
         struct inet6_dev *idev = rt->rt6i_idev;
 
-        if (dev != loopback_dev && idev != NULL && idev->dev == dev) {
-                struct inet6_dev *loopback_idev = in6_dev_get(loopback_dev);
+        if (dev != init_net.loopback_dev && idev != NULL && idev->dev == dev) {
+                struct inet6_dev *loopback_idev = in6_dev_get(init_net.loopback_dev);
                 if (loopback_idev != NULL) {
                         rt->rt6i_idev = loopback_idev;
                         in6_dev_put(idev);
@@ -1185,12 +1185,12 @@ int ip6_route_add(struct fib6_config *cfg)
         if ((cfg->fc_flags & RTF_REJECT) ||
             (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK))) {
                 /* hold loopback dev/idev if we haven't done so. */
-                if (dev != loopback_dev) {
+                if (dev != init_net.loopback_dev) {
                         if (dev) {
                                 dev_put(dev);
                                 in6_dev_put(idev);
                         }
-                        dev = loopback_dev;
+                        dev = init_net.loopback_dev;
                         dev_hold(dev);
                         idev = in6_dev_get(dev);
                         if (!idev) {
@@ -1894,13 +1894,13 @@ struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
         if (rt == NULL)
                 return ERR_PTR(-ENOMEM);
 
-        dev_hold(loopback_dev);
+        dev_hold(init_net.loopback_dev);
         in6_dev_hold(idev);
 
         rt->u.dst.flags = DST_HOST;
         rt->u.dst.input = ip6_input;
         rt->u.dst.output = ip6_output;
-        rt->rt6i_dev = loopback_dev;
+        rt->rt6i_dev = init_net.loopback_dev;
         rt->rt6i_idev = idev;
         rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
         rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c
index cc07216cfd59..15aa4c58c315 100644
--- a/net/ipv6/xfrm6_policy.c
+++ b/net/ipv6/xfrm6_policy.c
@@ -375,7 +375,7 @@ static void xfrm6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
 
         xdst = (struct xfrm_dst *)dst;
         if (xdst->u.rt6.rt6i_idev->dev == dev) {
-                struct inet6_dev *loopback_idev = in6_dev_get(loopback_dev);
+                struct inet6_dev *loopback_idev = in6_dev_get(init_net.loopback_dev);
                 BUG_ON(!loopback_idev);
 
                 do {